Ring binder



FIG. 1 is a perspective view of a ring binder, showing my new design;

FIG. 2 is a left side elevation thereof;

FIG. 3 is a right side elevation thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a front elevation thereof, the rear elevation being a mirror image thereof; and,

FIG. 6 is a bottom plan view thereof. 

The ornamental design for a ring binder, as shown and described. 